Hi @Nan Lei • Thank you for reaching out.
I understand that you are unable to create a service principal using Azure Portal by clicking on the Create Service Principal
link on the overview page of your app registration.
This must be due to some breaking change as I have used this link in the past to create service principal but it is no longer working for me as well. This is an issue with the UI as the "create service principal" is not a valid hyperlink and if you right-click on it, you will not get the options that are available on valid hyperlinks.
This is not a permissions issue as you can use the same account to create a service principal using Graph API or PowerShell. I have raised a ticket regarding this with the product team to get it addressed. Meanwhile, as a workaround, you can continue using Graph API/Powershell to create the service principals.
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